Development of TTI's Asphalt Compaction Monitoring System (0-6992-1)

In recent years, the Texas Department of Transportation has made significant progress with the development and implementation of new technologies to measure the uniformity of new hot mix asphalt layer construction. Early studies focused on the development of the Pave-IR system for checking temperature uniformity during mat placement. In Project 0-6992, researchers took this check one step further by developing an accurate global positioning system tracking system for compaction rolling so that the compaction effort applied can be monitored for 100 percent of the new surface. Additional sensors were also included in the system, including two temperature sensors and an accelermeter, to monitor whether the roller is vibrating. The new system can be mounted on any roller in a matter of minutes, and itprovides the roller operator with real-time color displays of:

• The number of passes of the entire mat.
• The compaction effectiveness (this study found that better compaction was found directly under the center portion of the roller than at the roller edges).
• The temperature at the first pass of the roller.

This report presents details of the hardware and software developed in this study. The system was field tested on a number of new overlay projects in Texas. Those results will be reported in later reports from this study.